This invention relates to a display of terms, for example, terms used for searching through electronic data base systems, and more specifically, to a method and apparatus for displaying search terms, selecting desired terms and obtaining records from a structured data base. The method and system are preferably applied to data bases that are indexed or formatted but, in a most general sense, it is applicable to any electronic data base.
Historically there are two ways of selecting records from a data base. One is called "command driven" and requires a user to formulate requests for records from the data base by typing instructions or "commands" that are syntactically correct according to the grammatical and spelling rules of the software used to access the particular data base. These rules are often complicated, extremely inflexible and are many times lacking in obvious meaning from the point of view of the user's normal English vocabulary and grammar. As an example, in one system a user might be required to type the term "SEL/na=Brown,*" to select records where Brown appears as the surname of the author, and where the given name is not specified. The software associated with the data base recognizes "SEL" as a search command, "na=" as a command identifying the author field or category in each record of the data base, and "Brown,*" as the search term. In another system, a user is required to type "S au/??Brown" to conduct the same type of search through a second data base, since the command syntax is different than the first software search system.
The second known method of searching through or making selections from a data base, usually called "menu driven", displays syntactically clear phrases describing the choices that can be made in formulating a search in a data base. These choices appear in a column as a list or "menu" of terms on the computer screen. A different menu is used for each decision making category. The user is expected to recognize the term that indicates the procedure he wants executed and type some simple, non-syntactic character to indicate this choice. Usually terms in menus are numbered and the user types the numeric character that corresponds to the chosen term.
In situations where more than one decision needs to be made in order for a particular procedure, i.e., search, to be executed, a choice on one menu may result in the appearance of additional menus that call for additional terms to be selected. Menu driven formats have the advantage of requiring a minimum amount of skill from the user. However, since it takes time for a computer screen to change from one menu display to another, menu driven selection procedures are slow in comparison to command driven procedures when multiple choices are being made. Also, when selections are made from several menus in succession the user may lose sight of or forget what decisions have been made and what decisions or selections could have been made if the decision path had taken a different direction.
The menu driven system can be combined with so-called "pop-up" or "pop-down" windows that display the men selections for an individual category. However, when the number of terms in the menu is great, this type of "pop-up" menu system is impractical due to the limited size of the video display screen. Further, if a large number of categories or fields are involved in the search, the size of the "pop-up" menu is further diminished if the user is to have an unobstructed view of all the categories available for selecting the search terms.
The present invention is an improvement on both command driven and menu driven selection procedures. It is a unique method in that it presents all possible decision making categories at the same time, i.e., simultaneously, and usually continuously on a single computer screen. All search term choices are displayed as meaningful, syntactically correct words or phrases. The invention utilizes any selected search term or search method decision previously made by the user to determine the most efficient order for requesting further input by the user in subsequent decision categories. The user makes selections from one category while having a visual record of choices selected in other previous categories and can change a term previously selected in a category without effecting the other choices or resubmitting earlier search term decisions.